For sale is a. Vintage Sinclair Gasoline porcelain sign that is a great piece to add to your gas collection. Featuring beloved characters like Popeye the sailor, this sign is perfect for any fan of the classic cartoon and the gas and oil industry. Whether you are displaying this sign as part of your collection in your man cave, shop, bar, or garage, or giving it as a gift, you can also browse my other auctions for more vintage gas, oil, aviation, automobile, motorcycle, and hunting signs. Vintage Sinclair Gasoline porcelain sign. 12 inches in diameter. Bright colors w/ porcelain on both sides.